Operations that involve the joining together of two or more pieces of material often require complex mechanisms for holding the various pieces of material relative to each other. These mechanisms become even more complicated when the pieces of material must be moved while they are being joined together. For instance, in a sewing operation, the pieces of material that are to be joined together must be held securely with respect to each other as they are guided underneath a sewing needle. The pieces of material (hereinafter collectively referred to as the workpiece) are guided underneath the sewing needle in such a manner as to define a series of successive stitching points. The sewing needle enters the workpiece at each of the thus defined stitching points and joins the pieces of material together. Any slippage of the workpiece within the clamping mechanism during the sewing operation will result in an erroneous stitch by the sewing needle. Furthermore, any misregistration of the workpiece when initially clamped will result in subsequent deviations from the predefined stitching points.
Clamping mechanisms which attempt to solve the above problems of work slippage and misregistration are often designed to conform to the shape of a specific sewing pattern that is to be sewn. These clamping mechanisms cannot be utilized to clamp a workpiece for the sewing of a substantially different pattern. On the other hand, clamping mechanisms which do allow for the sewing of substantially different patterns are usually quite complex in design. These latter mechanisms moreover require complicated, time-consuming procedures for inserting, aligning, and clamping the workpiece.